VSOP Observation codes

Observation codes for VSOP General Observing Time observations have the form

for example, v034b1. In turn:

• The first letter indicates which AO period the observation was proposed in: the letter `v' indicates the first AO period, and the letter `w' indicates the second and third AO periods.
• The three digits indicate the proposal number. There were 150 proposals received in response to the first AO, however due to the duplicate submission of one proposal the proposal numbers run from 001 to 151. For proposals with more than 26 experiments (see next item), 300 is added to the proposal code for the 27th and subsequent experiments. For A02, there were 95 proposals so proposal numbers run from 001 to 095. Proposals with more than 26 experiments (see next item) have 100 added to the 27th and subsequent experiments. w096a was a target of opportunity proposal. For AO3 there were 30 proposals and proposal codes run from w301 to w330. Proposal w330 had more than 26 experiments proposed and so w331 is used for the 27th and subsequent experiments.
• The following letter indicates the experiment within the proposal, with `a' denoting the first experiment, `b' the second, etc. As mentioned in the previous item, for experiments with more than 26 experiments, 300 is added to the proposal code, and the alphabetical sequence starts again from `a', so that the experiment following v047z is v347a. The one exception is proposal v127, which included too many sources for this rule to be followed. Experiments in this proposal start with v127 or v227 or v327 or v427. (Fortunately v027 was a more modest proposal!)
• For multi-epoch experiments, a final number is used to denote the different observations within each experiment. For instance, v034b1 is the first epoch of experiment v034b, and v034b2 the second. If no final digit appears, a single-epoch experiment was proposed.

Please note the nomenclature used for VSOP observations:

• An observation is a single continuous event, usually lasting for between 1~3 orbits.
• An experiment is one or more observations of a single source at a single frequency within a single proposal.

Observation codes for VSOP Survey Program observations have the form

for example, vs10x. The continuum component of the survey uses codes from vso1 to vs12.

Observation codes for VSOP Test and In-Orbit Checkout observations have the form

for example, vt801. Several sequences of numbers have been used as the long term schedule has evolved.